Nut



sept. 9,1941.

F. MCDERMQTT V NUT Filed Feb. 5, 1940 Patentedsept. 9, 1941y 2,255,673' NUT' Franklin McDermott, La Grange, Ill., assignor, by

mesne assignments, to Wagner Malleable Products Company, Decatur, Ill., a corporation of Delaware Application February 5,1940, Serial 'o. 317,362.

2 Claims.

My invention relates to vnuts which are more especially intended for use' in connecting threadless tubing or pipes' to an elctrical outlet or of two pipes, by means of suitable ttings or coupling elements which include the use of com.-`

paratively thin walled contractible split rings which are also adapted to be compressed into pipe gripping condition.

The invention has for its object the provision ofl a specially constructed nut which, in conjunction with the fitting or coupler, will have a f minimum amount of surface 'contact with one side or end of the split ring and will induce proper contraction f the split ring through the least possible frictional engagement .therewith and whereby a pipe gripping or holding relation.

A structure, or for connecting the unthreaded ends between the split ring and the pipe may be efiected, at least initially, by hand screwing of the nut onto the coupler'. s

The invention contemplates a sleeve type of nut provided with a convex radius or arcuate surface or shoulder on the inner face of the inturned flange and also having a co'mparatively wide machined or unthreaded surface at one end of the nut; namely an arcuate surface so formed that a very narrow or small rounded portion of the convexity will contact the adjacent end or side of the split ring, whether the latter be of arcuate or V-shape cross-section, and in conjunction with the usual beveled end ofthe fitting or coupler will cause the split ring to contract into pipe gripping condition; while the machined un'- threaded inner surface adjacent the convex shoulder on the flange is adapted to .contact the ring adjacent the crown or apex thereof and prevent outward expansion so that in the further screwing up of the nut, through the medium of awrench, the opposite ends or sides of the split improper support otiered by the threadsoi the nut, permits the ring to break down 'and to creep into the threads of the nut during the compression vof the ring necessary to obtain a pipe biting condition.

The objects of my invention are to overcome the conditions mentioned and to provider a nut which 4will present a small arcuate surface to the end or side'of the' split ring aording the least possible frictional contact therewith and also presenting a plain backing up surface for the crown of the ring during ring contracting and compressing operation.

The objects and advantages of my invention will all be fully4 comprehended from the detailed description of the accompanying drawing wherein:

Figure 1 is a side and sectional elevation of my improved nut.

Figure 2 is a longitudinal sectional View of a connector and the threadless end of a pipe secured together by a split'ring through the Y shoulder as at I2 against;` which the end of the tube or pipe Il abuts and with the outer end of the connector preferably beveled as shown at I3; the end of the connector being externally threaded to receive a sleeve nut i4 provided ywith the inwardly disposedflange I5 which defines an aperture approximating the outside diameter of the-tubing or pipe to be connected in place. ?-z-'-The pipe Il is secured in the connector I0 by the split ring I6, which may be either of arcuate comparatively large flat bearing surfaces on the flanges of the nuts are vpresented to the adjacent ends or sides of fthe split rings with the result that an undue amount of friction is produced between the rings and the nuts during screwing up of the latter; the extensive frictional contact tending to distort or twistQthe thin walledsplit rings, which, by reason .of the y' j l v I Y ycross-section' as shownin Figure .2, or of V-shape cross-section as shown at the right inr Figure 3; the ring being located within the nut vlwith its one side or end in contact with the beveled orice I3 of the connector element I0, while the other side or end of the ring is engaged by the 1(inner surfacepof the inturned flange of the nut I6.

lThe split rings Ii are of comparatively thin metal which may be readily contractedinto intimate holding engagement with the threadless pipe II when the nut I4 is screwedonto the externally threaded hub or end of the connector and which also are capable of being compressed \\or collapsed transversely to compensate for.

slight variations in pipes of a given diameter and to effect biting relation with the pipe; that is to say, the peripheral edges at opposite ends or sides of the ring are compressed into firm gripping relation with the threadless pipe.

In threadless pipe connecting means as at present in use the nuts are internally threaded throughout and are provided with flanges beveledlon their inner faces which present comparatively wide ring contacting surfaces and consequently have extensive frictional engagement with the ringswhich tends to vdistort or twist the thin walledy rings during nut tightening op- In installing the tubing orthreadless pipes, it is desirable initially to contract the clamping ring into holding engagement with the pipe by hand screwing of the nut until a proper position of the ttings and pipehave been determined. In order to readily accomplish the contraction of the ring into holding contact with the pipe -without the use of a Itool or wrench and also prevent ring distortion the flange o'thenut should be formed so as to present a very thinannular linev of contact with the ring.

I vobtain the desiredsmall contact between the split ring IB and the sleeve nut I4 by providing the latter with a convex radius on the inner face of the flange I5 as shown at I'I; the convex Isurface l1 extending circumferentially aboutthe inner face of the ilange I5 intermediate of the main wall of the nut and the orifice of the pipe receiving opening in the flange.

As shown in the drawing, the convexedsurface I'I is so formed that a very narrow rounded point of contact adjacent the perimeter of the split ring I6 is obtained, whereby a contracting With the smooth annular surface I8, the nut andthe ring move together during the screwing up of thenut and the ring cannot now into the roots of the threads.

My improved nut is equally adapted for use with connector elements employing split rings of somewhat different cross-setcional conguration as illustrated at the right in Figure 3 where a two pipe connector element or sleeve member I9 is shown connecting the adjacent ends of two aligned threadless pipes II; the opposite externally threaded ends of the connector element I9 being provided with nuts I4, I4 having the convex radius II -and the smooth unthreaded surface I8 on the inner face of each nut; the nut I4 at the left having an arcuate ring as shown in Figure 2, while the nut I4 at .the right hand end of the connector is shown with a split col- I lapsible ring IIa of V-shapecross-section.

the fittings and pipe by hand screwing the nutv The convex surface I'I of the nut approximates an arc of a circle whose center is disposed adjacent the point of juncture between the fiange'IS and the main body of the 'nut so as to present a comparativelysmall point of engagement with the split Aring-' namely an arcuate point having the least possible frictional con- When installing tubing or pipes of the type in question, it is customary to properly position onto the connector, which temporarily suciently closes or contracts the split ring into holding engagement with the pipe until any necessary v adjustments have been made and then tightly pressure on the ring is exerted which induces contraction of the ring through the exertion of very little power. It is also apparent that the convex face I1 presents an attenuated line of contact with the ring and consequently hasl the least possible frictional engagement therewith, with the result that distortion or any twisting tendency of the thin walled rings is prevented.

As previously'stated, the nuts of threadless pipe couplings as heretofore employed have been threaded interiorly throughout their lengths,

with thev result that when the nuts were screwed' up tightly with a wrench so as to cause the thin walled rings to be compressed transversely, the rings, being encircled by the threaded portionof the nut and hence not having a proper backing or support at their crown or points of maximum external diameter, have a tendency to break down and to become wedged in the roots of some of the threads. By reason ofv these conditions a proper fluid-tight and rm gripping relation with the pipes cannot be ensured. In order to overcome this undesirable condition I propose providing the nut with a comparatively wide smooth surface as shown at 'I8 which Vextends substantially throughout one-half of the ring width and aiords a backing or annular support and prevents radial outward movement or expansion of the ring and consequently induces. the perimeters of the ring at opposite sides to bite through the paint or enamel on the pipe and eil'ect proper fluid-tight.

and desired gripping relation' with the pipe.

screwing up the nut onto the connector through the use of a wrench, which causes a slight collapsing of the ring sides toward each other and also be positioned to exert pressure on the split rings in the general direction of the beveled end of the connector element and hence the convex surface of the nut must be' such that it will merely engage the rings at one side of the crown or major diameterof the rings. These functions are performed by the small annular curved or rounded convex surface of my improved nut.

What I claim is:

1. In combination with an externally threaded coupler member provided with a chamfered orice adapted toreceive the end of a threadless pipe and a thin walled metallic split ring of arched cross section whose opposite ends are adapted to eiect gripping engagement with a 'threadless pipe; a sleeve nut internally threaded at one end adapted to screw onto the coupler member, provided with an inturned ange about the pipe receiving aperture at the other end and an internal comparatively wide unthreaded cylindrical portion intermediate of the threads and said ange adapted to contact the ring adjacent its circumferential median line, the inner face of said ilange being provided with an annular convex surface; whose radius is connned within the body of the nut, adapted to effect anannular line adjacent its pipe gripping end to induce contraction and compression thereof.

2. A sleeve nut for use with an externally ,threaded pipe connector and an arched split ring adapted to grip the pipe, saidnut being internally threaded at one end to screw vonto the connector and having an inturned ilange at the other end provided on its inner face with an annular convex lsurface adapted to provide a t thin annularline contact with the adJacent side of the ring, the nut interior intermediate of said threads and said :danse being provided with a comparatively widek smooth surface of width substantially equal to one-half the width of the ring adapted to contact the crown of the ring and prevent outward radial movement thereof.

MCDERMOTI. 

